LOWER PALEOZOIC. 215 
NOTE. 
At the request of the editor, Mr. C. D. Walcott has made a 
collection of paragraphs from his interesting memoir in the 
March, April, and May numbers of the American Journal of 
Science (1888), on the "Taconic System of Emmons," which in 
his opinion presents a fair synopsis of his final conclusions.* 
Synopsis of Conclusions of Mr. C. D. Walcott 
ON THE " TaCONIC SySTEM OF EmMONS." 
The nomenclature employed in classifying geologic formations 
and terranes should be based upon priority of definition and upon 
the accuracy of the original observations ; the latter to be judged 
by the testimony of the formations within the areas where they 
were first made. If the original proposer of a name bases it 
upon such errors of observation and interpretation that subse- 
quent observers cannot verify his work, and the name can only 
be used by dropping a name proposed as the result of accurate 
observation and definition, the latter should be retained. 
I endeavored to make, in 1886, an argument for the use of 
the name Taconic for the Middle division of the Cambrian Sys- 
tem, but it failed in the light of later results of field work ; and 
now I think that geologic nomenclature will be benefited by 
dropping the name entirely. Based on error and misconception 
originally, and used in an erroneous manner since, it serves only 
to confuse the mind of the student, when applied to any forma- 
tion or terrane. There are several reasons for the foregoing con- 
clusions that perhaps it is best to here state. 
1st. — The name is not applicable. The Taconic range, from 
which the " Taconic System " was named, is not known to 
* lie says in a note accompanying these excerpts ; 
U. S. Geological Survey, 
Washington, D. C, May 26th, 1888. 
Dr. Persifor Frazer, 201 South Fifth Street, Philadelphia, Pa. 
My Dear Sir : I have put together the paragraphs you mention in your 
letter of the 24th inst., and added two others for your consideration. This must 
not be considered as a report from me, but simply as a suggestion to you. 
********* 
Truly yours, 
CHARLES D. WALCOTT. 
N. B. — The slips (3 pages) are herewith enclosed. — W. 
